1. Field of the Invention
The present invention relates to a thermal dispersing structure, and more particularly to a thermal dispersing structure applied to LED or SMD LED lights.
2. Description of Related Art
Theoretically, light emitting diode (LED) is a light source has longest lifespan, lowest heat, lowest chemical pollution and electricity consumption so that application of LED is the major trend of present illumination having environmental and energy-saving efficiency.
However, taking LEDs to make a conventional bulb still has some drawbacks as below:
1. The conventional LED bulb is a spot light source and thus usually performs halation phenomenon. Unlike halide bulb and tungsten bulb which are line light sources or high-pressure sodium lamp or fluorescent lamp (such as fluorescent light tube, compact fluorescent lamp), HID bulbs which are activated by sodium, mercury or xenon elements to perform planar light source, the spot light source of LED causes uneven LUX with great drops to the projecting surfaces it projects thereto and has poor illumination uniformity in comparison with the fluorescent light tube, compact fluorescent lamp and tungsten bulb especially serving as reading lights (as shown in FIGS. 1 to 4).
2. The conventional LED illumination lights all embed one or multiple LED units into one or multiple V-shaped recesses in a heat sink base. Although the V-shaped recesses adjust the projecting angles of the light from LED units, wide-angle light is also interrupted and transformed to refraction light. In other words, light from LED spot light source out of direct light range within the V-shaped recess will be refracted by sidewalls therein to cause irregular and uneven fraction light which also damps the uniformity in illumination (as shown in FIGS. 5 and 6).
3. The conventional LED bulbs or lamps with high lumens all need heat sink base to disperse heat, wherein LED lamps having low watts (take 1 W as an example) can sufficiently disperse or conduct heat by attaching heat sink base (as shown in FIGS. 5 and 6). However, LED lamps having high watts (for example, 3 W or 5 W) or a small substrate collecting multiple 1 W LED units can not sufficiently disperses the high heat even by attaching the heat sink base made of copper or aluminum boards. Therefore, the conventional LED lamps cannot protect the LED units with chips within the limitation temperature (60 to 65° C.) to decrease their decay and thus to stabilize their lifespan.